Differential pressure transmitters, as shown in FIG. 1, have long been known in the art. Typically, a differential pressure transmitter system as shown in FIG. 1 is used with a pipeline 10 in which there is a flowing media which needs to be measured as to flow rate. A very accurate and economical method of measuring flow is to install an orifice 12 in the pipeline 10. Orifice 12 causes a differential pressure as media is forced through the small opening of orifice 12, which differential is sensed by a transmitter 14 through process pressure signal lines 16 and 18. The amount of differential pressure developed is a square root function of the flow rate. Consequently, by knowing the size of the precision hole in the orifice plate, and by obtaining a precision measurement of the differential pressure, the flow rate can be calculated with greater than 1% accuracy.
FIG. 2 illustrates the transmitter system shown in FIG. 1 in greater detail. It is conventional to provide a valve manifold 50 to interface with the two process pressure signal lines from the orifice 12 by utilizing gaskets 56, adapters 58 and nipples 60. Transmitter 14 is then interfaced with the above valve manifold 50 with gaskets 68 and four bolts 72 (one bolt shown in FIG. 2). In addition, a mounting bracket 74 is provided with four bolts 76 (one bolt shown in FIG. 2) to bolt onto the transmitter 14. Transmitter 14 is clamped onto a 2" pipe rack 78 with U-bolt 80, which physically supports the hardware.